Fix the "address already in use" issue

doh-client/client.go

@@ -154,24 +154,24 @@ func (c *Client) newHTTPClient() error {
 }
 
 func (c *Client) Start() error {
-	result := make(chan error, len(c.udpServers)+len(c.tcpServers))
+	results := make(chan error, len(c.udpServers)+len(c.tcpServers))
 	for _, srv := range append(c.udpServers, c.tcpServers...) {
 		go func(srv *dns.Server) {
 			err := srv.ListenAndServe()
 			if err != nil {
 				log.Println(err)
 			}
-			result <- err
+			results <- err
 		}(srv)
 	}
 
-	for i := 0; i < cap(result); i++ {
+	for i := 0; i < cap(results); i++ {
-		err := <-result
+		err := <-results
 		if err != nil {
 			return err
 		}
 	}
-	close(result)
+	close(results)
 	return nil
 }
 

doh-server/main.go

@@ -43,8 +43,5 @@ func main() {
 	}
 
 	server := NewServer(conf)
-	err = server.Start()
+	_ = server.Start()
-	if err != nil {
-		log.Fatalln(err)
-	}
 }

doh-server/server.go

@@ -75,26 +75,29 @@ func (s *Server) Start() error {
 	if s.conf.Verbose {
 		servemux = handlers.CombinedLoggingHandler(os.Stdout, servemux)
 	}
-	listeners := make(chan error, len(s.conf.Listen))
+	results := make(chan error, len(s.conf.Listen))
 	for _, addr := range s.conf.Listen {
-		if s.conf.Cert != "" || s.conf.Key != "" {
+		go func(addr string) {
-			go func() {
+			var err error
-				listeners <- http.ListenAndServeTLS(addr, s.conf.Cert, s.conf.Key, servemux)
+			if s.conf.Cert != "" || s.conf.Key != "" {
-			}()
+				err = http.ListenAndServeTLS(addr, s.conf.Cert, s.conf.Key, servemux)
-			continue
+			} else {
-		}
+				err = http.ListenAndServe(addr, servemux)
-		go func() {
+			}
-			listeners <- http.ListenAndServe(addr, servemux)
+			if err != nil {
-		}()
+				log.Println(err)
+			}
+			results <- err
+		}(addr)
 	}
 	// wait for all handlers
-	for i := 0; i < cap(listeners); i++ {
+	for i := 0; i < cap(results); i++ {
-		err := <-listeners
+		err := <-results
 		if err != nil {
 			return err
 		}
 	}
-	close(listeners)
+	close(results)
 	return nil
 }